The Seiko 4N21-0430 is a watch model based on the 4N21 movement.
Parts List
| 190A02S20A | crystal - crystal |
| 30M81NA5 | crown - crown |
| 6M30Z3SNWD | crown - crown |
| 30M81NA4 | crown - crown |
| 0H1800B01 | case back gasket - case back gasket |
| 0F160BAA5 | case back gasket - case back gasket |
| 0F160BA1S | case back gasket - case back gasket |
| AC004BA11 | case back gasket - crown and stem gasket |
| D1A9CM | band - band |
| RB27A | band - band |
| D1A9CM-LK00 | band - link |
| RB26A | band - metal band |
| RB27A-BK00 | clasp - clasp |
| 3BA090F1BNS | others - second hand |
| 1BA050A7BNS | others - hour hand |
| 2BA077A5BNS | others - minute hand |
| 3EA070A0BDG | others - second hand |
| 1BB050YCBNG | others - hour hand |
| 2BB075YEBNG | others - minute hand |
| 81181459 | others - bracelet fixing pipe |
| 81190075 | others - bracelet fixing pipe |
| 81602669 | others - bracelet fixing pin |
| 82832635 | others - case ring |
| 4N210430XBA | others - case |
| 82353459 | others - bezel |
| 4N210430 | others - case back |
| 4N210430XBB | others - case |
| 4N210430XBC | others - case |
| 4N210430XBF | others - case |
| 4N210430XBK | others - case |
| 4N21043061A | others - case |
| 4N210430XBE | others - case |
| 4N210870XS24 | others - dial |
| 4N210871XS14 | others - dial |
| 4N212700XA14 | others - dial |
| 4N216 | others - machine code |
| 4N2164 | others - machine code |
| D1A9CM-BKPP | others - spring bar for buckle/clasp |
| 0351155 | others - winding stem |
| D1A9CM-LKPN | others - pin for link |
| 07T95JCH | others - hour hand |
| 07T95JGM | others - minute hand |
| 08SC55VG | others - second hand |
| 3EA075A0BDG | others - second hand |
| 3DA075AABDG | others - second hand |